New Tech Solves Longstanding Challenges for Self-Healing Materials

3D printed thermoplastic on woven-carbon fiber reinforcement.
Credit: North Carolina State University

Engineering researchers have developed a new self-healing composite that allows structures to repair themselves in place, without having to be removed from service. This latest technology resolves two longstanding challenges for self-healing materials, and can significantly extend the lifespan of structural components such as wind-turbine blades and aircraft wings.

“Researchers have developed a variety of self-healing materials, but previous strategies for self-healing composites have faced two practical challenges,” says Jason Patrick, corresponding author of the research paper and an assistant professor of civil, construction and environmental engineering at North Carolina State University.

“First, the materials often need to be removed from service in order to heal. For instance, some require heating in an oven, which can’t be done for large components or while a given part is in use. Second, self-healing only works for a limited period. For example, the material might be able to heal a few times, after which its self-repairing properties would significantly diminish. We’ve come up with an approach that addresses both of those challenges in a meaningful way, while retaining the strength and other performance characteristics of structural fiber-composites.”

Largest Potentially Hazardous Asteroid Detected in Eight Years

Twilight observations with the U.S. Department of Energy-fabricated Dark Energy Camera at Cerro Tololo Inter-American Observatory in Chile, a program of NSF’s NOIRLab, have enabled astronomers to spot three near-Earth asteroids, or NEAs, hiding in the glare of the sun. These NEAs are part of an elusive population that lurks inside the orbits of Earth and Venus. One of the asteroids is the largest object that is potentially hazardous to Earth to be discovered in the last eight years.
Image Credit: DOE/FNAL/DECam/CTIO/NOIRLab/NSF/AURA/J. da Silva/Spaceengine

Twilight observations with the US Department of Energy-fabricated Dark Energy Camera at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF's NOIRLab, have enabled astronomers to spot three near-Earth asteroids (NEA) hiding in the glare of the Sun. These NEAs are part of an elusive population that lurks inside the orbits of Earth and Venus. One of the asteroids is the largest object that is potentially hazardous to Earth to be discovered in the last eight years.

An international team using the Dark Energy Camera (DECam) mounted on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF’s NOIRLab, has discovered three new near-Earth asteroids (NEAs) hiding in the inner Solar System, the region interior to the orbits of Earth and Venus. This is a notoriously challenging region for observations because asteroid hunters have to contend with the glare of the Sun.

By taking advantage of the brief yet favorable observing conditions during twilight, however, the astronomers found an elusive trio of NEAs. One is a 1.5-kilometer-wide asteroid called 2022 AP7, which has an orbit that may someday place it in Earth’s path. The other asteroids, called 2021 LJ4 and 2021 PH27, have orbits that safely remain completely interior to Earth’s orbit. Also, of special interest to astronomers and astrophysicists, 2021 PH27 is the closest known asteroid to the Sun. As such, it has the largest general-relativity effects [1] of any object in our Solar System and during its orbit its surface gets hot enough to melt lead.

Ghost of a giant star

This image shows a spectacular view of the orange and pink clouds that make up what remains after the explosive death of a massive star — the Vela supernova remnant. This detailed image consists of 554 million pixels, and is a combined mosaic image of observations taken with the 268-million-pixel OmegaCAM camera at the VLT Survey Telescope, hosted at ESO’s Paranal Observatory.   OmegaCAM can take images through several filters that each let the telescope see the light emitted in a distinct color. To capture this image, four filters have been used, represented here by a combination of magenta, blue, green and red. The result is an extremely detailed and stunning view of both the gaseous filaments in the remnant and the foreground bright blue stars that add sparkle to the image. 
Hi-Res Zoomable Image
Credit: ESO/VPHAS+ team. Acknowledgement: Cambridge Astronomical Survey Unit

A spooky spider web, magical dragons or wispy trails of ghosts? What do you see in this image of the Vela supernova remnant? This beautiful tapestry of colors shows the ghostly remains of a gigantic star, and was captured here in incredible detail with the VLT Survey Telescope, hosted at the European Southern Observatory’s (ESO’s) Paranal site in Chile.

The wispy structure of pink and orange clouds is all that remains of a massive star that ended its life in a powerful explosion around 11 000 years ago. When the most massive stars reach the end of their life, they often go out with a bang, in an outburst called a supernova. These explosions cause shock waves that move through the surrounding gas, compressing it and creating intricate thread-like structures. The energy released heats the gaseous tendrils, making them shine brightly, as seen in this image.

In this 554-million-pixel image, we get an extremely detailed view of the Vela supernova remnant, named after the southern constellation Vela (The Sails). You could fit nine full Moons in this entire image, and the whole cloud is even larger. At only 800 light-years away from Earth, this dramatic supernova remnant is one of the closest known to us.

A better way to tell which species are vulnerable

Intertidal ecosystems containing species of mussels, barnacles, and algae were one of the systems with fluctuating populations analyzed by the team. They developed a new way to detect species that are vulnerable to perturbations, such as waves and storms that affect intertidal ecosystems.
Credits: Courtesy of the researchers | Massachusetts Institute of Technology

Wildfires, floods, pollution, and overfishing are among the many disruptions that can change the balance of ecosystems, sometimes endangering the future of entire species. But evaluating these ecosystems to determine which species are most at risk, in order to focus preservation actions and policies where they are most needed, is a challenging task.

Most such efforts assume that ecosystems are essentially in a state of equilibrium, and that external perturbations cause a temporary shift before things eventually return to that equilibrium state. But that assumption fails to account for the reality that ecosystems are often in flux, with the relative abundances of their different components shifting on timetables of their own. Now, a team of researchers at MIT and elsewhere have come up with a better, predictive way of evaluating these systems in order to rank the relative vulnerabilities of different species, and to detect species that are under threat but could otherwise go unnoticed.

Contrary to conventional ways of making such rankings today, they found, the species with the lowest population numbers or the steepest decline in numbers — criteria typically used today — are sometimes not the ones most at risk.

The findings are reported today in the journal Ecology Letters, in a paper by MIT associate professor of civil and environmental engineering Serguei Saavedra, recent doctoral student Lucas Medeiros PhD ’22, and three others.

Just like humans, more intelligent jays have greater self-control

A study has found that Eurasian jays can pass a version of the ‘marshmallow test’ – and those with the greatest self-control also score the highest on intelligence tests.
Photo Credit: Takashi Yanagisawa

This is the first evidence of a link between self-control and intelligence in birds.

Self-control - the ability to resist temptation in favor of a better but delayed reward – is a vital skill that underpins effective decision-making and future planning.

Jays are members of the corvid family, often nicknamed the ‘feathered apes’ because they rival non-human primates in their cognitive abilities. Corvids hide, or ‘cache’, their food to save it for later. In other words, they need to delay immediate gratification to plan for future meals. The researchers think this may have driven the evolution of self-control in these birds.

Self-control has been previously shown to be linked to intelligence in humans, chimpanzees and – in an earlier study by these researchers – in cuttlefish. The greater the intelligence, the greater the self-control.

The new results show that the link between intelligence and self-control exists across distantly related animal groups, suggesting it has evolved independently several times.

Of all the corvids, jays in particular are vulnerable to having their caches stolen by other birds. Self-control also enables them to wait for the right moment to hide their food without being seen or heard.

New Material for Perovskite Solar Cells Proposed in Russia

Scientists have proposed a new type of material for transporting electrons in perovskite solar cells.
 Photo Credit: Vladimir Petrov

Experts from the Ural Federal University and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences, together with other Russian scientists, have proposed a new type of material for one of the solar cell cells. The discovered compounds will significantly reduce the cost of solar cell production. An article with the results of the study was published in the New Journal of Chemistry.

Perovskite solar cells (PSCs) are a promising alternative to the familiar silicon cells, providing the same amount of energy with 180 times less material thickness. Their production technology is much simpler and cheaper than that of silicon cells. The problem with PSCs is their lack of stability. One of the most effective solutions today, as explained by the experts, is the selection of new materials that ensure the transport of the charge carriers after it is obtained in the perovskite layer itself.

The scientific team of the Ural Federal University and the Institute of Organic Synthesis of the Ural Branch of the Russian Academy of Sciences proposed a new type of material for transporting electrons in the PSCs, which has a number of advantages. According to the authors, with the new material they managed to achieve solar energy conversion efficiency of 12%, which is comparable with the average indicators of market analogues.

Step by step

Berkeley researchers may be one step closer to making robot dogs our new best friends. Using advances in machine learning, two separate teams have developed cutting-edge approaches to shorten in-the-field training times for quadruped robots, getting them to walk — and even roll over — in record time.

In a first for the robotics field, a team led by Sergey Levine, associate professor of electrical engineering and computer sciences, demonstrated a robot learning to walk without prior training from models and simulations in just 20 minutes. The demonstration marks a significant advancement, as this robot relied solely on trial and error in the field to master the movements necessary to walk and adapt to different settings.

“Our work shows that training robots in the real world is more feasible than previously thought, and we hope, as a result, to empower other researchers to start tackling more real-world problems,” said Laura Smith, a Ph.D. student in Levine’s lab and one of the lead authors of the paper posted on arXiv.

In past studies, robots of comparable complexity required several hours to weeks of data input to learn to walk using reinforcement learning (RL). Often, they also were trained in controlled lab settings, where they learned to walk on relatively simple terrain and received precise feedback about their performance.

NUS researchers devise revolutionary technique to generate hydrogen more efficiently from water

An NUS team led by Assoc Prof Xue Jun Min (center) has found that light can trigger a new mechanism in a catalytic material used extensively in water electrolysis (held up by Mr. Zhong Haoyin), where water is broken down into hydrogen and oxygen. The result is a more energy-efficient method of obtaining hydrogen. Dr Vincent Lee Wee Siang (right) is a member of the research team.
 Credit: National University of Singapore

The team’s discovery that light can trigger a brand new electro-catalytic mechanism of water electrolysis could improve affordability of hydrogen as source of clean energy

A team of researchers from the National University of Singapore (NUS) have made a serendipitous scientific discovery that could potentially revolutionize the way water is broken down to release hydrogen gas - an element crucial to many industrial processes.

The team, led by Associate Professor Xue Jun Min, Dr Wang Xiaopeng and Dr Vincent Lee Wee Siang from the Department of Materials Science and Engineering under the NUS College of Design and Engineering (NUS CDE), found that light can trigger a new mechanism in a catalytic material used extensively in water electrolysis, where water is broken down into hydrogen and oxygen. The result is a more energy-efficient method of obtaining hydrogen.

This breakthrough was achieved in collaboration with Dr Xi Shibo from the Institute of Sustainability for Chemicals, Energy and Environment under the Agency for Science, Technology and Research (ASTAR); Dr Yu Zhigen from the Institute of High-Performance Computing under ASTAR; and Dr Wang Hao from the Department of Mechanical Engineering under the NUS CDE.

Overcoming resistance to colon cancer treatment

Colorectal cancer cells after treatment with FOLFORIXI chemotherapy for 34 weeks. Cell fibers (in green) and nuclei (in blue).
Credit: UNIGE-Nowak-Sliwinka

Colorectal cancer is one of the most common cancers. Its treatment is mainly based on chemotherapy. However, over time, chemotherapy induces resistance in the majority of patients, who end up being unresponsive to the drugs. As a result, the five-year survival rate for those affected is still low. After succeeding in reproducing this resistance in the laboratory, a team from the University of Geneva (UNIGE) has found a way to overcome it. The team has used an optimized combination of drugs belonging to the class of tyrosine kinase inhibitors, which take different pathways to attack cancer cells than chemotherapy. These results, to be found in the journal Cancers, open up new avenues for overcoming treatment resistance and for developing new therapies that are more targeted than chemotherapy.

Colorectal cancer is the third most diagnosed cancer in the world and second only to lung cancer in terms of mortality. It most often develops from the age of 50 in the terminal part of the colon. It results from a change in the DNA of certain cells present in this organ. These cells become cancerous and proliferate in an uncontrolled manner until they form a primary tumor. As in many cancers, these cells can migrate to other parts of the body and form secondary tumors. This is known as metastatic cancer.

While genetics play a role in the development of the disease, the presence of inflammatory bowel diseases (e.g. Crohn’s disease) and certain dietary habits (alcohol, red meat) are also risk factors. In the case of a primary tumor, treatment is based on surgery and chemotherapy. In the case of secondary tumors, it is based on a combination of chemotherapies. These treatments are non-targeted and aggressive. They cause significant side effects. They also lead to progressive resistance to treatment in the majority of patients.

Considering COVID a hoax is ‘gateway’ to belief in conspiracy theories

Data showed one strong trend suggesting that financial distress during the lockdown could have been a factor in adopting conspiracy theory beliefs about the pandemic – even among those who started off with low levels of conspiracist ideation.
Photo Credit: Lara Jameson

Belief that the COVID-19 pandemic was a hoax – that its severity was exaggerated or that the virus was deliberately released for sinister reasons – functions as a “gateway” to believing in conspiracy theories generally, new research has found.

In the two-survey study, people who reported greater belief in conspiracy theories about the pandemic – for which there is no evidence – were more likely to later report they believed that the 2020 presidential election had been stolen from Donald Trump through widespread voter fraud, which is also not true. Participants’ overall inclination to believe in conspiracy theories also increased more among those who reported believing COVID-19 was a hoax.

Based on the results, the Ohio State University researchers have proposed the “gateway conspiracy” hypothesis, which argues that conspiracy theory beliefs prompted by a single event lead to increases in conspiratorial thinking over time.

Preliminary evidence suggests a sense of distrust may function as one trigger.

“It’s speculative, but it appears that once people adopt one conspiracy belief, it promotes distrust in institutions more generally – it could be government, science, the media, whatever,” said senior author Russell Fazio, professor of psychology at Ohio State. “Once you start viewing events through that distrustful lens, it’s very easy to adopt additional conspiracy theories.”